Two separate orders at same time merged into one

[Symphony]

This has happened three times this month

If we get two separate checkouts completed at the same time – both through a certain payment method – then the order is strangely merged. This results in one customer’s order being visible to them, but corrupted with some elements of the other customer’s order in place of the correct data (eg. Delivery address, or products). In the case of the second customer’s order: it simply vanishes.

Our system therefore shows one corrupted order, instead of two seperate orders

It is almost as if both orders were trying to get the same order ID and the result was this corruption.

It is only because we receive payment notification emails from our merchant provider that we spotted the issue.

Any suggestions?

[Symphony]

In the case of today's example:

The system shows customer 1 has placed an order, with the correct billing address details, but with customer 2's items (at customer 2's price) and customer 2's delivery details.

Customer 2 has no orders showing on the system, but we have a payment confirmation external to PS confirming a payment received for the item that was erroneously showing on customer 1's order.

Edited July 29, 2020 by Symphony (see edit history)

[Guest]

Disable memcache in performance and recompile template

[Symphony]

Thats great many thanks - really appreciate your input.

Before I test, please could you advise if disabling memcache will cause any other issues as a result? We do have Litespeed Cache enabled.

Many thanks,

Dave

[Guest]

Don't use Memcache at all !!!

[Symphony]

I've just gone to try what you suggest, and it seems that we don't have memcache enabled. In fact, I can't find any referent to memcache at all.

The only cache that is current enabled is Litespeed, which is handled via a separate module and then on the server.

[Guest]

And did you try to disable the Litespeed module?

[Symphony]

I've not done, although that does significantly affect the performance of the website.

DO you believe Litespeed may be the cause?

[Guest]

And how else do you know that the module is OK?
If you turn it off and the problems disappear, it is clear that this is caused by the module.

[Symphony]

The difficulty is recreating the problem:

We have had it happen a total of four times - once about four months ago, and three times in the last 5-6 weeks.

The only common theme is that it happens when two orders occur at the same time. However, we have had many other orders occur at the same time with no problems. 

So to turn off Litespeed will create a 'Schrödinger' situation where the result may be that we don't see the issue recur....but it never would have occurred anyway.

And given that it could be months before the problem happens again, the truth is that turning off Litespeed will probably not help us identify. 

[Guest]

So look in the box to see if the cat is alive!
Take the cat out of the box and feed her.

If something is causing you a problem and you know what is causing you the problem, then it is up to you what you do with the problem.
Do you want to use a third-party tool?
So use it.
If you have a problem with a third-party tool, contact the developer who is affected.
Your error is not related to the core of Prestashop, but is caused by a third party.
So I would take the topic solved for me for free.
Eliminating your problem, modifying modules, etc. belong to the JOB!